Chemically defined generation of human cardiomyocytes

Area of Science:

• Stem Cell Biology
• Cardiovascular Research
• Biochemistry

Background:

• Current human induced pluripotent stem cell (hiPSC) cardiac differentiation methods use complex, undefined media, limiting mechanistic studies of cardiomyogenesis.
• Undefined components in differentiation media pose challenges for understanding the precise molecular requirements for cardiomyocyte development.

Purpose of the Study:

• To develop an optimized, chemically defined cardiac differentiation strategy for hiPSCs.
• To simplify the medium composition for hiPSC-cardiomyocyte differentiation to facilitate mechanistic investigations.

Main Methods:

• Utilized hiPSCs cultured under chemically defined conditions on synthetic matrices.
• Systematically optimized a chemically defined medium comprising RPMI 1640, L-ascorbic acid 2-phosphate, and rice-derived recombinant human albumin.
• Employed small molecule-based induction for differentiation.

Main Results:

• Achieved contractile cardiomyocyte sheets with up to 95% TNNT2(+) cells.
• Obtained a high yield of up to 100 cardiomyocytes per input pluripotent cell.
• Demonstrated efficacy across 11 diverse hiPSC lines.

Conclusions:

• Established a chemically defined platform for hiPSC cardiac specification.
• This platform enables detailed study of cardiomyocyte macromolecular and metabolic needs.
• Provides a minimal system for investigating cardiomyocyte maturation and subtype specification.